Veritas Volume Manager 5.0 Administrator's Guide (September 2006)

148 Administering dynamic multipathing (DMP)
Administering DMP using vxdmpadm
# /opt/VRTS/bin/vxdmpadm enable ctlr=second_cntlr
5 Re-enable the plex associated with the device:
# /opt/VRTS/bin/vxplex -g diskgroup att volume plex
This command takes some time depending upon the size of the mirror set.
Renaming an enclosure
The vxdmpadm setattr command can be used to assign a meaningful name to an
existing enclosure, for example:
# vxdmpadm setattr enclosure enc0 name=GRP1
This example changes the name of an enclosure from enc0 to GRP1.
Note: The maximum length of the enclosure name prefix is 25 characters. The name must
not contain an underbar character (_).
The following command shows the changed name:
# vxdmpadm listenclosure all
ENCLR_NAME ENCLR_TYPE ENCLR_SNO STATUS
============================================================
other0 OTHER OTHER_DISKS CONNECTED
jbod0 X1 X1_DISKS CONNECTED
GRP1 ACME 60020f20000001a90000 CONNECTED
Configuring the response to I/O failures
By default, DMP is configured to retry a failed I/O request up to 5 times for a single path.
To display the current settings for handling I/O request failures that are applied to the
paths to an enclosure, array name or array type, use the
vxdmpadm getattr command:
# vxdmpadm getattr \
{enclosure enc-name|arrayname name|arraytype type} \
recoveryoption
See “Displaying recoveryoption values” on page 151 for more information.
The following example displays the I/O request failure setting for the paths to the
enclosure enc0:
# vxdmpadm getattr enclosure enc0 recoveryoption
The vxdmpadm setattr command can be used to configure how DMP responds to
failed I/O requests on the paths to a specified enclosure, disk array name, or type of array.
The following form of the command sets a limit for the number of times that DMP will
attempt to retry sending an I/O request on a path:
# vxdmpadm setattr \
{enclosure enc-name|arrayname name|arraytype type} \
recoveryoption=fixedretry retrycount==n